When we want to respond to an answer (or thread, I don't know how it names), there is only a simple text input, without possibility to format the text (no line break, no paragraph, quote etc.)
Why it's important to you :
Because I'd like to give more precision without editing the text after submition
Giving a real text area, with editing options, the same as when we answer a question.
I guess someone else gave this idea before.